Portable telephone



FIG. 1 is a front, top and right side perspective view of a portable telephone showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a bottom plan view thereof; and,

FIG. 5 is a rear elevational view thereof. 

The ornamental design for a "portable telephone", as shown and described. 